The report deals with retrospective research in possible induction of relapse by breast reconstruction carried out simultaneously with surgery for breast cancer. The end results were compared between cases of modification of radical mastectomy combined with reconstruction (n=124) and controls who underwent surgery for cancer alone (n=379). Standard radio- and systemic therapy was used. Median follow-up was 64 months. Local and general recurrence as well as relapse-free and overall survival rates were identical. Multivariate analysis failed to establish any correlation between primary breast reconstruction and relapse. Nor did it increase the risk of the development of the latter.